JP4696289B2 - Thermocouple temperature sensor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a thermocouple temperature sensor and a manufacturing method thereof.

Conventionally, thermocouple temperature sensors have been used as temperature measurement means for solids and fluids. A thermocouple type temperature sensor uses a thermoelectromotive force according to a temperature difference between two contacts forming a closed circuit, and a wire or conductor pattern forming a closed circuit is generally made of metal. Made materials were used.
As a conventional technique using a metal material, for example, (Patent Document 1) states that “a linear film patterned with a first metal on a base made of an electrically insulating material is different from the first metal. A thermocouple temperature sensor including a linear film patterned with a second metal is disclosed.
(Patent Document 2) discloses “a wafer with a temperature sensor in which metal wires such as chromel and alumel are arranged on the surface side”.
(Patent Document 3) states that “a resin film having a metal linear conductor pattern such as copper formed by etching and a metal linear conductor pattern such as nickel formed by etching are formed. A temperature sensor having a coupling portion in which linear conductor patterns are connected by alternately laminating and heat-pressing a resin film is disclosed.
In addition, as a technique for forming a thermocouple using a material other than metal, (Patent Document 4) states that “on a substrate, a semiconductor ceramic made of iron silicide and a glass of about 5% by weight for improving the adhesion between the substrate and the substrate. And a temperature sensor element in which a thermocouple layer containing the component is laminated.
Japanese Unexamined Patent Publication No. 64-778 JP 2002-257635 A JP 2003-14553 A JP 2005-55338 A

However, the above conventional techniques have the following problems.
(1) The techniques disclosed in (Patent Document 1) to (Patent Document 3) have the problem of lacking in corrosion resistance and chemical resistance because metal wires and conductor patterns are used as thermocouples. Was. Even though they are made of metal, there are materials having excellent corrosion resistance and chemical resistance, such as chromel / alumel and platinum / platinum rhodium, but they have a problem of lack of cost.
(2) Since thermocouples made of metallic materials have poor oxidation resistance, when used under conditions such as in exhaust gas, they must be protected by covering them with a metal protective tube like a sheathed thermocouple. It cannot be used, and has a problem that it is bulky and difficult to downsize.
(3) The thermoelectromotive force generated in the closed circuit formed of two types of metal wires and conductor patterns is, for example, 6.5 μV / K when the material is platinum / platinum rhodium, and the thermocouple specified by JIS. Among them, even in the case of chromel / constantan having the largest thermoelectromotive force, it is 63 μV / K, so that it has a problem that sensitivity is low for detecting a slight temperature change, and precise temperature detection is difficult. It was.
(4) In order to obtain a thermocouple layer, the technique disclosed in (Patent Document 4) is obtained by laminating a thermocouple pattern layer containing iron silicide on a substrate and then firing in a vacuum at 1100 to 1180 ° C. for about 3 hours. Then, since it is necessary to perform an operation of sintering in an argon atmosphere at 700 to 850 ° C. for about 12 hours to make a semiconductor, there is a problem that it is complicated and lacks productivity.
(5) When two types of conductors made of crystallized semiconductor material such as iron silicide or metal material are joined to make a thermocouple, it is relatively difficult to join a fine conductor. It was necessary to use a wide conductor, and the joint was wide. When the temperature of the target area smaller than the size of the joint is measured, an error is included, and thus there is a problem that the temperature of the fine target area cannot be accurately measured. In addition, if the joint is processed using focused ion beam (FIB) processing or laser processing in order to reduce the size of the formed joint, the crystallized semiconductor material or metal material is cleaved due to damage such as ion irradiation. Etc. occur, and the joint portion deteriorates and is easily disconnected, and thus there is a problem that the joint portion cannot be finely processed.

The present invention solves the above-described conventional problems, and is excellent in corrosion resistance and chemical resistance, and also in oxidation resistance, so that the characteristics are not easily deteriorated even in exhaust gas, and it is excellent in durability. Can be manufactured by extremely simple methods such as sputtering, glow discharge, sol-gel method, etc., so there is no need for complicated operations such as heating to semiconductors for a long time and miniaturization. Therefore, an object of the present invention is to provide a thermocouple temperature sensor that can accurately measure the temperature of a fine target region.
Further, the present invention can be manufactured by a very simple method such as melting and quenching of crystalline solid, vapor deposition method, sputtering method, glow discharge method, sol-gel method, etc. It is possible to finely adjust electrical characteristics by miniaturization and surface modification by performing fine processing such as etching and surface modification. It aims at providing the manufacturing method of the thermocouple type temperature sensor from which a type temperature sensor is obtained.

In order to solve the above-described conventional problems, the thermocouple temperature sensor and the manufacturing method thereof according to the present invention have the following configurations.
The thermocouple temperature sensor according to claim 1 of the present invention includes a first conductor formed of a first electron conductive oxide glass, and the first electron conductivity bonded to the first conductor. A second conductor formed of an oxide glass and a second electron conductive oxide glass having a different composition and / or heat treatment condition , the first electron conductive oxide glass and the second electron The conductive oxide glass is a vanadate glass .
With this configuration, the following effects can be obtained.
(1) Since it is made of electron-conducting oxide glass, it has excellent corrosion resistance and chemical resistance, as well as excellent oxidation resistance, and its characteristics are not easily degraded even in exhaust gas without using a metal protective tube. Excellent durability.
(2) Electron conductive oxide glass can be manufactured by extremely simple methods such as melting and quenching of crystalline solids, vapor deposition, sputtering, glow discharge, sol-gel, etc. Thermocouples can be formed by differentiating the composition and heat treatment temperature of the two types of electron-conducting oxide glasses that form the body. Therefore, after baking at 1100 to 1180 ° C., heating at 700 to 850 ° C. for a long time makes a semiconductor. It is excellent in productivity without requiring complicated operations such as
(3) Since the electron-conductive oxide glass is not cleaved even when processed using focused ion beam (FIB) processing, laser processing, etc., it can be easily processed to ultra fine processing of about 1 μm or less. It is possible to accurately measure the temperature of a fine target area.
(4) Vanadate glass has high electrical conductivity, and can be made to exhibit high electrical conductivity of 10 ⁻¹ S · cm ⁻¹ or more at room temperature by virtue of heat treatment after vitrification. Since the response is fast and the thermoelectromotive force is large, the temperature can be detected with high sensitivity and high accuracy. By applying heat treatment, it is possible to remove the distortion of the glass skeleton and reduce the activation energy (band gap) at which electrons hop, and also distribute the electrons in the vanadate glass to high energy levels, Since it is possible to reduce the thermal energy (activation energy) necessary for hopping electrons, it is assumed that the electrical conductivity can be increased.

Here, as the electron conductive oxide glass, semiconducting glass containing transition metal oxides such as vanadium, iron, manganese, titanium, and tungsten, oxide photoconductivity containing CdO, PbO, etc. and exhibiting photoconductivity. Glass is used, for example, V ₂ O ₅ —P ₂ O ₅ system, V ₂ O ₅ —P ₂ O ₅ —BaO system, WO ₂ —P ₂ O ₅ system, CdO—B ₂ O ₃ —SiO ₂ system. , CdO—Al ₂ O ₃ —GeO ₂ , PbO—Bi ₂ O ₃ —SiO ₂ , PbO—Al ₂ O ₃ —GeO _{2 and the} like.

As the first electron conductive oxide glass and the second electron conductive oxide glass, glasses having different components can be appropriately selected from the electron conductive oxide glasses. Even glass composed of the same component can be used as glass having a different composition as long as the components have different quantitative relationships.
Further, glass having different components and quantitative relationships between the components, and glasses having the same quantitative relationship between the components and the components can be used as thermocouples by changing the heat treatment conditions of the respective glasses. Examples of the heat treatment conditions include a heat treatment temperature and a heat treatment holding time.
As described in Japanese Patent Application Laid-Open No. 2003-34548, it is known that even an electron conductive oxide glass having the same composition can have different electrical conductivities by performing heat treatment. This is presumed to be due to the fact that the distortion of the glass skeleton is removed by heat treatment, and the activation energy (band gap) at which the electrons of the two types of electron conductive oxide glass hop can be made different. For this reason, it is guessed that it can be used as a thermocouple by joining these two kinds of electron conductive oxide glasses.

  As a means for producing an electron conductive oxide glass, an electron conductive oxide which is a solid having a glass transition temperature or lower without being crystallized after changing a mixture of a crystalline solid such as a transition metal oxide into a liquid or gas. There is no particular limitation as long as the glass can be made. For example, an electron conductive oxide glass can be obtained by heating and melting a mixture of crystalline solids and then rapidly cooling the mixture. Alternatively, the electron conductive oxide glass can be obtained by once changing the crystalline solid to a vapor state by vapor deposition, sputtering, CVD, glow discharge, or the like. Moreover, an electron conductive oxide glass can also be obtained by passing through a gel like the sol-gel method.

The first conductor and the second conductor are manufactured by rapidly cooling a melt obtained by heating and melting a mixture of crystalline solids in a mold or a cooling drum to form an electron conductive oxide glass into a linear shape or the like. A part of the produced two kinds of electron conductive oxide glasses can be brought into contact with each other and welded to be joined. Moreover, before quenching a melt, it can also join by making a part of melt of two types of electron conductive oxide glasses contact each other, and quenching rapidly, maintaining this state. Moreover, it can be joined also by adhere | attaching 2 types of manufactured electroconductive oxide glasses using a conductive adhesive etc.
In addition, when a glass layer is formed on an insulating substrate by vapor deposition, sputtering, glow discharge, sol-gel method, etc., the two types of electron conductive oxide glasses should be formed so as to be in contact with each other. The first conductor and the second conductor can also be joined.
In addition, the first electron conductive oxide glass and the second electron conductor oxide glass can be bonded to each other with the same composition without joining the first electron conductor oxide glass and the second electron conductor oxide glass. The first electron-conducting oxide glass and the second electron-conducting oxide glass are formed by integrally irradiating with ions and then partially differing in composition. Can also be joined.

The formed first conductor and second conductor can be subjected to fine processing such as etching and surface modification by ion irradiation such as focused ion beam processing and ion implantation. As a result, the first conductor and the second conductor can be miniaturized and the electrical characteristics can be finely adjusted by surface modification, and a highly accurate thermocouple temperature sensor can be obtained.
In addition, this thermocouple type temperature sensor can be used in a temperature range from 0 ° C. or lower to the glass transition temperature.

Here, the vanadate glass is an oxide glass containing vanadium as a main component or an auxiliary component. In addition to vanadium, an alkali metal such as potassium or sodium, an alkaline earth metal such as barium or magnesium, boron, Those containing oxides of one or more constituent elements of phosphorus, cerium, tin, lead, copper, iron and the like are used.
Among these, those containing vanadium, barium and iron oxides are preferably used. This can form a glass skeleton in which atoms of vanadium, barium, and iron are three-dimensionally related, can exhibit high electrical conductivity due to electron hopping, and is further tetravalent in the glass skeleton. This is because the pentavalent vanadium and the trivalent iron can be arranged, so that the probability of electron hopping is increased and the electrical conductivity can be increased.

Here, the ratio of barium oxide (BaO), vanadium oxide (V ₂ O ₅ ), and iron oxide (Fe ₂ O ₃ ) in the vanadate glass is not particularly limited as long as it exhibits a glass transition phenomenon. In particular, the molar ratio (B: V) of barium oxide (B) to vanadium oxide (V) is preferably 5:90 to 35:50.
Thereby, the following actions are obtained.
(1) Since a glass skeleton having a three-dimensional structure having vanadium as a main skeleton can be formed, the electrical conductivity can be dramatically increased by performing heat treatment.
(2) The variation in the electric conductivity of the electron conductive oxide glass before the heat treatment is reduced and it is difficult to crystallize by the heat treatment, so that the electric conductivity of the electron conductive oxide glass after the heat treatment can be kept within a predetermined range. Excellent production stability.
Here, when the molar ratio (B: V) is smaller than 5:90, it becomes difficult to form a glass skeleton having a three-dimensional structure, and it becomes difficult to obtain a homogeneous electron conductive oxide glass. When B: V) is larger than 35:50, vitrification becomes difficult, crystallization is facilitated by heat treatment, and good conductivity is not expressed, which is not preferable.

The molar ratio (F: V) of iron oxide (F) to vanadium oxide (V) in the vanadate glass is preferably 5:90 to 15:50.
Thereby, the following actions are obtained.
(1) Since a three-dimensional glass skeleton having vanadium as the main skeleton can be formed, the electrical conductivity can be dramatically increased by heat treatment.
Here, when the molar ratio (F: V) is smaller than 5:90, it is difficult to vitrify, and when the molar ratio (F: V) is larger than 15:50, it is difficult to obtain a homogeneous vanadate glass. Neither is preferred.

Furthermore, vanadium oxide vanadate glass _{(V 2 O} 5), barium oxide (BaO), vanadium oxide in the ternary iron oxide _{(Fe 2 O 3) (V} 2 O 5) is from 40 to 98 mol % Preferably 60 to 85 mol% is suitable. As it becomes less than 60 mol%, it tends to be difficult to maintain a glass skeleton having vanadium as the main skeleton, and it is difficult to obtain high electrical conductivity. In particular, since the content of subcomponents is reduced, adjustment functions such as electrical conductivity and mechanical properties due to the subcomponents tend to be reduced. In particular, when the amount is less than 40 mol% or more than 98%, these tendencies are remarkable, which is not preferable.
The barium oxide (BaO) in the three-component system in the vanadate glass is 1 to 40 mol%, preferably 10 to 30 mol%. As the amount becomes less than 10 mol%, homogenous vitrification tends to be difficult, and as the amount exceeds 30 mol%, mechanical strength decreases and vitrification tends to become difficult. In particular, when the amount is less than 1 mol% or more than 40 mol%, these tendencies are remarkable, which is not preferable.
The iron oxide (Fe ₂ O ₃ ) in the three-component system in the vanadate glass is 1 to 20 mol%, preferably 5 to 20 mol%. As the content becomes less than 5 mol%, the contribution to the electron hopping by the valence electrons of iron tends to be reduced, and the electrical conductivity tends to be difficult to improve. Moreover, since it will become difficult to vitrify because mechanical strength will fall when it exceeds 20 mol%, it is unpreferable.
In particular, the molar ratios of vanadium oxide (V ₂ O ₅ ), barium oxide (BaO), and iron oxide (Fe ₂ O ₃ ) are in the range of 60 to 85 mol%, 10 to 30 mol%, and 5 to 20 mol%, respectively. In this case, by applying heat treatment to the vanadate glass, the electrical conductivity at room temperature can be increased by several orders of magnitude to 10 ⁻¹ S · cm ⁻¹ or more, and the responsiveness of the thermocouple temperature sensor Can be increased, which is preferable.

The vanadate glass may be added with additives such as AgI, NaI, Ag, Ag ₂ O, In ₂ O ₃ , SnO, SnO ₂ and ReO ₂ . This is because the electrical conductivity can be increased by the effect of the additive. In addition to AgI, NaI, Ag, etc., a reduction inhibitor such as CeO ₂ may be added. Thereby, it can prevent that additives, such as AgI, NaI, Ag, are reduced, and can maintain high electrical conductivity.

The heat treatment conditions applied to the vanadate glass are those in which the vitrified vanadate glass is heated and maintained in a temperature range above the glass transition temperature and below the melting point, preferably above the crystallization temperature and below the melting point. Is used.
Here, as the heat treatment temperature becomes lower than the crystallization temperature of the vanadate glass, the thermal energy given to the vanadate glass is small, so the rate of increase in electrical conductivity is small and the rate of increase tends to vary. When the strength becomes less than the glass transition point, this tendency becomes remarkable, which is not preferable. Moreover, when the heat treatment temperature exceeds the melting point of the vanadate glass, melting of the oxide glass and precipitation of crystals are promoted, and the electrical conductivity is lowered, which is not preferable.

  As a means for performing the heat treatment, for example, when an electric furnace or the like is set to a heat treatment temperature in advance and the temperature in the furnace becomes constant, the vanadate glass is placed in the furnace and immediately after the target time has elapsed. A vanadate glass is taken out from an electric furnace or the like and cooled by a member such as a fluid such as air, water, ice water, a cooled copper plate or stainless steel plate, or a copper or stainless steel roller. Alternatively, after reheating the vanadate glass in a furnace such as an electric furnace for a certain period of time, gradually lowering the temperature in the furnace or gradually moving away from the heating source in the furnace, the vanadate glass is placed in the furnace. What is allowed to cool is used. The inside of the furnace where the heat treatment is performed can be an atmosphere of an inert gas such as air, nitrogen, or argon.

The glass transition point, crystallization temperature, and melting point can be determined by actually measuring the vanadate glass by differential thermal analysis (DTA), differential scanning calorimetry (DSC), or the like. Moreover, it can also obtain | require by performing the thermodynamic calculation etc. using the state diagram of the estimated component.
When the crystallization temperature is determined by differential thermal analysis (DTA), the temperature at the central point or the bottom side temperature of the exothermic peak of crystallization is defined as the crystallization temperature. Moreover, when calculating | requiring melting | fusing point by a differential thermal analysis (DTA), let the temperature in the center point of the endothermic peak in higher temperature than crystallization temperature be a melting | fusing point.

  The holding time in the heat treatment temperature region under the heat treatment conditions can be appropriately set to an optimal time so that the electrical conductivity of the vanadate glass that has undergone the heat treatment is increased. The holding time varies depending on the composition, heat capacity, and heat treatment temperature of the vanadate glass, but is set to 1 to 180 minutes, for example. When the holding time is shorter than 1 minute, the thermal energy given to the vanadate glass is small, so the rate of increase in electrical conductivity is small, and the rate of increase varies, and when longer than 180 minutes, crystals precipitate. Or melting, the electrical conductivity may decrease and the productivity may decrease.

The method of manufacturing a thermocouple temperature sensor according to claim 2 of the present invention includes: (a) a first conductor formed of a first electron conductive oxide glass; and the first conductor that is joined to the first conductor. A conductor forming step of forming a first electron conductive oxide glass and a second conductor formed of a second electron conductive oxide glass having a different composition and / or heat treatment condition; and (b) the first An ion irradiation step of performing ion irradiation on one conductor and / or the second conductor , wherein the first electron conductive oxide glass and the second electron conductive oxide glass are vanadate glasses. It has the composition which is.
With this configuration, the following effects can be obtained.
(1) Since the first conductor and the second conductor are formed of the electron conductive oxide glass, the crystalline solid can be melted and rapidly cooled, vapor deposition, sputtering, glow discharge, sol-gel method, etc. Since it can be manufactured, it does not require a complicated operation such as heating at 700 to 850 ° C. for a long time after baking at 1100 to 1180 ° C., and excellent in productivity.
(2) Since the first conductor and the second conductor are provided with an ion irradiation process for irradiating ions, fine processing such as etching and surface modification can be performed, and the first conductor and the second conductor Since the electric characteristics can be finely adjusted by miniaturization or surface modification, a fine and highly accurate thermocouple temperature sensor can be obtained.
(3) Since the first or second electron conductive oxide glass is vanadate glass, when heat treatment is performed, the holding time in the treatment temperature region may be 1 to 180 minutes, and the heat treatment is performed in a short time. Electric conductivity can be increased.

  Here, the electron conductive oxide glass, the first conductor, and the second conductor in the conductor forming step are the same as those described in claim 1, and thus the description thereof is omitted.

As ion irradiation means in the ion irradiation step, ion implantation, focused ion beam processing, or the like is used.
For the purpose of etching, a liquid metal such as Ga or a rare gas such as Ar, Xe, or Kr is used as an ion species for irradiating the first conductor or the second conductor. In this case, transition metals such as V, Fe, Mn, Ti, and W, which are constituent elements of the electron conductive oxide glass, are used.

Invention of Claim 3 of this invention is a manufacturing method of the thermocouple type temperature sensor of Claim 2 , Comprising: The ionic species irradiated to said 1st conductor and / or said 2nd conductor is It has a configuration that is vanadium.
With this configuration, in addition to the operation obtained in the second aspect , the following operation can be obtained.
(1) By irradiating vanadium ions, the ratio of tetravalent and pentavalent vanadium ions present in the vanadate glass can be adjusted, and electrical characteristics such as thermoelectromotive force can be adjusted with high accuracy.

Here, 10 ² to 10 ⁵ ions / cm ² is suitably used as the irradiation amount (dose amount) of vanadium ions, and 1 to 30 KeV is suitably used as the irradiation energy. When the irradiation amount (dose amount) of vanadium ions is less than 10 ² ions / cm ² or the irradiation energy is less than 1 KeV, the change in the electrical properties of the vanadate glass is poor, and the ion irradiation time becomes longer and the productivity is increased. Is not preferable. Further, even if the irradiation amount (dose amount) of vanadium ions is larger than 10 ⁵ ions / cm ² or the irradiation energy is larger than 30 KeV, the ion irradiation effect is increased and the ion irradiation effect is hardly changed. It is not preferable because it lacks energy saving.

  After the vanadium ion irradiation, heat treatment is preferably performed at a temperature below the softening point of the glass. This is to stabilize the glass skeleton and the electrical characteristics.

As described above, according to the thermocouple temperature sensor and the manufacturing method thereof of the present invention, the following advantageous effects can be obtained.
According to the invention of claim 1,
(1) Since it is made of electron-conducting oxide glass, it has excellent corrosion resistance and chemical resistance, as well as excellent oxidation resistance, and its characteristics are not easily degraded even in exhaust gas without using a metal protective tube. A thermocouple type temperature sensor with excellent durability can be provided.
(2) Electron conductive oxide glass can be manufactured by extremely simple methods such as melting and quenching of crystalline solids, vapor deposition, sputtering, glow discharge, sol-gel, etc. Thermocouples can be formed by differentiating the composition and heat treatment temperature of the two types of electron-conducting oxide glasses that form the body. Therefore, after baking at 1100 to 1180 ° C., heating at 700 to 850 ° C. for a long time makes a semiconductor. Therefore, it is possible to provide a thermocouple type temperature sensor excellent in productivity without requiring a complicated operation.
(3) Since the electron-conductive oxide glass is not cleaved even when processed using focused ion beam (FIB) processing, laser processing, etc., it can be easily processed to ultra fine processing of about 1 μm or less. It is possible to provide a thermocouple type temperature sensor that can accurately measure the temperature of a fine target region.
(4) Vanadate glass has high electrical conductivity, and can be made to exhibit high electrical conductivity of 10 ⁻¹ S · cm ⁻¹ or more at room temperature by virtue of heat treatment after vitrification. Since the response is fast and the thermoelectromotive force is large, it is possible to provide a thermocouple temperature sensor with high sensitivity and high accuracy.

According to invention of Claim 2 ,
(1) Since the first conductor and the second conductor are formed of the electron conductive oxide glass, the crystalline solid can be melted and rapidly cooled, vapor deposition, sputtering, glow discharge, sol-gel method, etc. A method of manufacturing a thermocouple temperature sensor having excellent productivity without requiring a complicated operation such as heating to 700 to 850 ° C. for a long time after baking at 1100 to 1180 ° C. Can be provided.
(2) Since the first conductor and the second conductor are provided with an ion irradiation process for irradiating ions, fine processing such as etching and surface modification can be performed, and the first conductor and the second conductor Since the electrical characteristics can be finely adjusted by miniaturization or surface modification, a method of manufacturing a thermocouple temperature sensor that can obtain a thermocouple temperature sensor that is fine and highly accurate can be provided.
(3) When the heat treatment is performed, the holding time of the heat treatment temperature region is set to 1 to 180 minutes, so that it is possible to provide a method of manufacturing a thermocouple temperature sensor that can increase the electrical conductivity by a short heat treatment.

According to invention of Claim 3 , in addition to the effect of Claim 2 ,
(1) A thermocouple type that can adjust the ratio of tetravalent and pentavalent vanadium ions present in the vanadate glass by irradiating vanadium, and can accurately adjust the electrical characteristics such as thermoelectromotive force. A method for manufacturing a temperature sensor can be provided.

Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples.
Example 1
First, in order to prepare a sample for differential thermal analysis, barium oxide (BaO) is 20 mol%, divanadium pentoxide (V ₂ O ₅ ) is 70 mol%, and ferric trioxide (Fe ₂ O ₃ ) is Each reagent-grade reagent was weighed so that the total amount was 10 g at 10 mol%, mixed in an agate mortar, and then placed in a platinum crucible. The mixture in the platinum crucible was heated and melted in the atmosphere for 90 minutes in an electric furnace heated to 1000 ° C. to obtain a melt for differential thermal analysis. This melt was poured onto a stainless steel plate having a thickness of 10 mm and cooled to room temperature to obtain a glass solidified into a plate shape.
The glass was cut into a rod shape to prepare a sample, and differential thermal analysis (DTA) was performed. Differential thermal analysis (DTA) was performed at a heating rate of 10 ° C./min in a nitrogen atmosphere using α-alumina as a reference material. As a result of differential thermal analysis, it was found that the glass transition temperature was 328 ° C., the crystallization temperature was 392 ° C., and the melting point was 540 ° C.

Next, in order to produce a thermocouple type temperature sensor, similarly, 20 mol% of barium oxide (BaO), 70 mol% of divanadium pentoxide (V ₂ O ₅ ), and ferric trioxide (Fe ₂ O _3). ) Was weighed so that the total amount would be 10 g and the total amount was 10 g, and was similarly melted in a platinum crucible to obtain a melt for a thermocouple temperature sensor. A platinum boat (hereinafter referred to as the first boat) having a width of 3 mm, a length of 25 mm, and a depth of 6 mm was prepared, and the first boat was heated to 350 ° C. in an electric furnace and then taken out from the electric furnace. About half of the melt was poured into a solid and solidified.
After returning the first boat in which the melt was solidified to the electric furnace maintained at 350 ° C. again, the temperature of the electric furnace was raised to 500 ° C. above the crystallization temperature of the glass and below the melting point over 60 minutes. . After performing a heat treatment for holding the electric furnace at 500 ° C. for 20 minutes, the electric furnace was turned off and the first boat was allowed to cool in the electric furnace. After the inside of the electric furnace was cooled to room temperature, the first boat was taken out from the electric furnace, and the glass solidified in a rod shape (first electron conductive oxide glass) was taken out from the first boat.
The rod-shaped glass (first electron conductive oxide glass) taken out is put in a half of another platinum boat (hereinafter referred to as a second boat) having a width of 3 mm, a length of 50 mm, and a depth of 6 mm. 2 boats were placed in an electric furnace maintained at 350 ° C. and heated, then removed from the electric furnace and poured the remainder of the melt into the other half of the second boat, glass (first electronically conductive oxide glass) The melt for the second electron-conducting oxide glass was brought into contact with the end face of the glass.
After returning the second boat into the electric furnace maintained at 350 ° C. again, the temperature of the electric furnace was raised to 400 ° C., which is approximately the same as the crystallization temperature of glass, over 30 minutes. After performing the heat processing which hold | maintains an electric furnace at 400 degreeC for 60 minute (s), the electric furnace was switched off and the 2nd boat was stood to cool in an electric furnace. When the inside of the electric furnace is cooled to room temperature, the second boat is taken out from the electric furnace, and from the second boat, the first conductor formed of the first electron conductive oxide glass, the first conductor, A thermocouple temperature of Example 1 comprising: a second conductor formed of a second electron-conducting oxide glass that is bonded and has the same composition as the first electron-conducting oxide glass but having the same heat treatment conditions The sensor was removed.

FIG. 1 is a perspective view of a thermocouple temperature sensor according to the first embodiment.
In the figure, 1 is a thermocouple temperature sensor of Example 1, 2 is a first conductor formed of a first electron conductive oxide glass, and 3 is a first electron conductor bonded to the first conductor 2. This is a second conductor formed of a second electron conductive oxide glass having the same composition but different heat treatment conditions from the conductive oxide glass.
The thickness of the thermocouple temperature sensor of Example 1 was 3 mm, the width was 3 mm, the joint between the first conductor and the second conductor was not peeled off, and no defects such as pinholes were observed. .

In order to measure the thermoelectromotive force of the thermocouple temperature sensor of Example 1, when the junction is heated to 75 ° C., the end is held at 25 ° C. and the temperature difference is 50 ° C., the gap between both ends The generated thermoelectromotive force was 67 mV. On the other hand, when calculated from the JIS thermoelectromotive force table, the thermoelectromotive force of the chromel-alumel thermocouple (K thermocouple) at the same temperature difference is 2.1 mV, and the thermoelectromotive force of the chromel-constantan thermocouple (E thermocouple). The power is 3.2 mV.
Therefore, the thermoelectromotive force of the thermocouple type temperature sensor of Example 1 is about 30 times that of the chromel-alumel thermocouple and about 20 times that of the chromel-constantan thermocouple, so that a remarkably high thermoelectromotive force can be realized. It was revealed.

  In addition, in the manufacturing method of the thermocouple type temperature sensor of Example 1, the melt for 2nd electron conductive oxide glass was added to the end surface of the glass (1st electron conductive oxide glass) put into the boat. After the pouring contact, this boat was put into an electric furnace and subjected to heat treatment, but the heat treatment method is not limited to this method. For example, when glass is taken out from a boat, the first electron conductive oxide glass and the second electron conductive oxide glass are inserted into separate small tubular heaters, respectively, and each is heat-treated under different conditions. is there. In this case, the same effect can be obtained.

(Example 2)
Except that the junction of the first conductor and the second conductor of the thermocouple temperature sensor of Example 1 was cut with a focused ion beam using gallium as an ion source and refined to a width of 10 μm and a thickness of 300 μm. In the same manner as in Example 1, the thermocouple type temperature sensor of Example 2 was obtained.
When the junction of the thermocouple temperature sensor of Example 2 is heated to 75 ° C, while the end is held at 25 ° C and the temperature difference is 50 ° C, the thermoelectromotive force generated between both ends is also implemented. The voltage was about 60 mV which was almost the same as in Example 1.
From the above, it is clear that the thermocouple type temperature sensor of this embodiment not only has a high thermoelectromotive force, but is very easy to perform microfabrication, and therefore can accurately measure the temperature of a fine target region.

(Example 3)
First, to prepare a sample for differential thermal analysis, barium oxide (BaO) is 30 mol%, vanadium pentoxide _(V 2 _{O 5) or} 60 mol%, diiron trioxide _(Fe 2 _{O 3)} is Each reagent-grade reagent was weighed so that the total amount was 10 g at 10 mol%, mixed in an agate mortar, and then placed in a platinum crucible. The mixture in the platinum crucible was heated and melted in the atmosphere for 90 minutes in an electric furnace heated to 1000 ° C. to obtain a melt for differential thermal analysis. This melt was poured onto a stainless steel plate having a thickness of 10 mm and cooled to room temperature to obtain a glass solidified into a plate shape.
The glass was cut into a rod shape to prepare a sample, and differential thermal analysis (DTA) was performed. Differential thermal analysis (DTA) was performed at a heating rate of 10 ° C./min in a nitrogen atmosphere using α-alumina as a reference material. As a result of differential thermal analysis, it was found that the glass transition temperature was 356 ° C., the crystallization temperature was 433 ° C., and the melting point was 563 ° C.
Next, in order to produce a first conductor of the thermocouple type temperature sensor, likewise barium oxide (BaO) is 30 mol%, vanadium pentoxide (V 2 _{O 5) or} 60 mol%, ferric oxide ( Each reagent-special reagent was weighed so that the Fe ₂ O ₃ ) was 10 mol% and the total amount was 10 g, and was similarly melted in a platinum crucible to obtain a melt for the first conductor.
Similarly, for making the second conductors of the thermocouple type temperature sensor, barium oxide (BaO) is 20 mol%, vanadium pentoxide _(V 2 _{O 5) or} 70 mol%, diiron trioxide (Fe ₂ O ₃ ) is 10 mol% and the total amount is 10 g. Each reagent grade reagent is weighed so as to have the same composition as in Example 1, and similarly melted in a platinum crucible to obtain a melt for the second conductor. Obtained.
A first boat similar to that in Example 1 was heated to 350 ° C. in an electric furnace, and then the first boat was taken out of the electric furnace and poured into the melt for the first conductor. After the melt for the first conductor solidified, the solidified product was placed in half of the second boat, and the melt for second conductor was poured into the other half of the second boat.
After returning the second boat into the electric furnace maintained at 350 ° C. again, the temperature of the electric furnace was increased to 500 ° C. above the crystallization temperature of the two types of glass and below the melting point over 60 minutes. After performing the heat processing which hold | maintains an electric furnace at 500 degreeC for 60 minute (s), the electric furnace was switched off and the 2nd boat was stood to cool in an electric furnace. After the inside of the electric furnace is cooled to room temperature, the second boat is taken out from the electric furnace, the first conductor formed of the first electron conductive oxide glass, and the first electron joined to the first conductor. The thermocouple type temperature sensor of Example 3 including a second conductor formed of a second electron conductive oxide glass having a composition different from that of the conductive oxide glass but having the same heat treatment conditions was taken out.

  In order to measure the thermoelectromotive force of the thermocouple temperature sensor of Example 3, when the junction was heated to 75 ° C., while the end was held at 25 ° C. and the temperature difference was 50 ° C., between both ends The generated thermoelectromotive force was 35 mV. Therefore, the thermoelectromotive force of the thermocouple temperature sensor of Example 3 is about 20 times that of the chromel-alumel thermocouple at the same temperature difference, and about 10 times that of the chromel-constantan thermocouple. It became clear that can be realized.

Example 4
Special reagent grades such that barium oxide (BaO) is 20 mol%, divanadium pentoxide (V ₂ O ₅ ) is 70 mol%, diiron trioxide (Fe ₂ O ₃ ) is 10 mol% and the total amount is 10 g. Each reagent was weighed and placed in a platinum crucible. The mixture placed in the platinum crucible was melted by heating in the atmosphere for 90 minutes in an electric furnace heated to 1000 ° C. Half of the melt was poured into the first boat described in Example 1 and rapidly cooled to below the glass transition temperature, and then removed from the first boat to obtain a rod-shaped first electron conductive oxide glass. Half of the remaining melt was poured out into the first boat, rapidly cooled to below the glass transition temperature, and then taken out to obtain a rod-like second electron conductive oxide glass.
Next, the first electron-conducting oxide glass was reheated in the atmosphere at 400 ° C. which is not lower than the crystallization temperature and not higher than the melting point for 1 hour. Further, the second electron conductive oxide glass was reheated in the atmosphere at 400 ° C., which is not lower than the crystallization temperature and not higher than the melting point, for 30 minutes.
After applying a conductive adhesive (Dotite, manufactured by Fujikura Kasei Co., Ltd.) to the end face of the first electron conductive oxide glass that has been reheated, the end face of the second electron conductive oxide glass is abutted and 400 Heated at 30 ° C. for 30 minutes for bonding, the first conductor formed of the first electron conductive oxide glass, and the second electron conductive oxidation with different heat treatment conditions from the first electron conductive oxide glass The thermocouple type temperature sensor of Example 4 provided with the 2nd conductor joined with the 1st conductor formed with physical glass was obtained.

FIG. 2 is a perspective view of the thermocouple temperature sensor according to the fourth embodiment.
In the figure, 1a is the thermocouple temperature sensor of Example 4, 2a is the first conductor formed of the first electron conductive oxide glass, 3a is the first electron conductive oxide glass and the heat treatment conditions are A second conductive material made of a second electron conductive oxide glass which is different but has the same composition, 4 is a conductive adhesive formed by joining the first conductive material 2a and the second conductive material 3a to form a joint. It is.
When the junction of the thermocouple temperature sensor of Example 4 is heated to 75 ° C., while the end is held at 25 ° C. and the temperature difference is 50 ° C., the thermoelectromotive force generated between both ends is 35 mV. there were. Therefore, the thermoelectromotive force of the thermocouple type temperature sensor of Example 4 is about 20 times that of the chromel-alumel thermocouple at the same temperature difference, and about 10 times that of the chromel-constantan thermocouple. It became clear that can be realized.

(Example 5)
Vanadium ions were implanted into the first conductor of the thermocouple temperature sensor of Example 2 at an irradiation energy of 20 KeV and a dose of 10 ³ ions / cm ² . Next, heat treatment was performed for 30 minutes at 400 ° C. below the softening point in an electric furnace. Thereby, the thermocouple type temperature sensor of Example 5 was obtained.
When the junction of the thermocouple temperature sensor of Example 5 is heated to 75 ° C, while the end is held at 25 ° C and the temperature difference is 50 ° C, the thermoelectromotive force generated between both ends is about It was 130 mV. This is a value different from the thermoelectromotive force of the thermocouple temperature sensor of Example 2 by about 70 mV.
Thereby, it became clear that thermoelectromotive force can be adjusted by irradiating vanadium ion.

  According to the above examples, since it can be produced by an extremely simple method such as melting and quenching of a crystalline solid, it is excellent in productivity without requiring complicated operation, and has a high thermoelectromotive force and high sensitivity. Further, since it was possible to easily perform fine processing such as etching, it became clear that a fine and highly accurate thermocouple temperature sensor could be obtained.

  The present invention relates to a thermocouple temperature sensor and a method for producing the same, and has excellent corrosion resistance and chemical resistance, and also excellent oxidation resistance, so that the characteristics are hardly deteriorated even in exhaust gas, and the crystalline solid is rapidly cooled. Can be manufactured by extremely simple methods such as vapor deposition, sputtering, glow discharge, sol-gel, etc., so that it does not require complicated operations such as heating to semiconductors for a long time and has excellent productivity Temperature sensors can be provided and can be manufactured by extremely simple methods such as melting and quenching of crystalline solids, vapor deposition, sputtering, glow discharge, sol-gel, etc. It is excellent in productivity without requiring complicated operations, and by performing fine processing such as etching and surface modification, it is possible to finely adjust electrical characteristics by miniaturization and surface modification. Precision thermocouple type temperature sensor can be provided a method for producing a thermocouple type temperature sensor obtained.

The perspective view of the thermocouple type temperature sensor of Example 1. The perspective view of the thermocouple type temperature sensor of Example 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Thermocouple type temperature sensor 2,2a 1st conductor 3,3a 2nd conductor 4 Conductive adhesive

Claims (3)

A first conductor formed of the first electron conductive oxide glass, and a second electron bonded to the first conductor and having a different composition and / or heat treatment condition from the first electron conductive oxide glass. A second conductor formed of conductive oxide glass , wherein the first electron conductive oxide glass and the second electron conductive oxide glass are vanadate glasses. Thermocouple temperature sensor. (A) a first conductor formed of a first electron conductive oxide glass, and a composition and / or heat treatment condition different from that of the first electron conductive oxide glass bonded to the first conductor. A conductor forming step of forming a second conductor formed of two electron conductive oxide glasses; and (b) an ion irradiation step of performing ion irradiation on the first conductor and / or the second conductor. And the first electron-conductive oxide glass and the second electron-conductive oxide glass are vanadate glasses. The method for manufacturing a thermocouple temperature sensor according to claim 2, wherein the ion species irradiated to the first conductor and / or the second conductor is vanadium.

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